ArmPkg/BdsLib: Added support for FDT alignment through PcdArmLinuxFdtAlignment

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>



git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@14274 6f19259b-4bc3-4df7-8a09-765794883524

ArmPkg/ArmPkg.dec

@@ -2,7 +2,7 @@
 # ARM processor package.
 #
 # Copyright (c) 2009 - 2010, Apple Inc. All rights reserved.<BR>
-# Copyright (c) 2011 - 2012, ARM Limited. All rights reserved.
+# Copyright (c) 2011 - 2013, ARM Limited. All rights reserved.
 #
 #    This program and the accompanying materials
 #    are licensed and made available under the terms and conditions of the BSD License
@@ -137,8 +137,6 @@
   # 0xC00 = cp10 | cp11
   gArmTokenSpaceGuid.PcdArmNsacr|0xC00|UINT32|0x00000039
   
-  gArmTokenSpaceGuid.PcdArmNonSecModeTransition|0x0|UINT32|0x0000003E
-
   # System Memory (DRAM): These PCDs define the region of in-built system memory
   # Some platforms can get DRAM extensions, these additional regions will be declared
   # to UEFI by ArmPLatformPlib   
@@ -167,9 +165,6 @@
   gArmTokenSpaceGuid.PcdArmLinuxKernelMaxOffset|0x08000000|UINT32|0x0000001F
   # The Linux ATAGs are expected to be under 0x4000 (16KB) from the beginning of the System Memory
   gArmTokenSpaceGuid.PcdArmLinuxAtagMaxOffset|0x4000|UINT32|0x00000020
-  # If the fixed FDT address is not available, then it should be loaded the below the kernel
-  # The recommandation from the Linux kernel is to have the FDT below 16KB
-  gArmTokenSpaceGuid.PcdArmLinuxFdtMaxOffset|0x4000|UINT32|0x00000023
 
   #
   # ARM Architectural Timer
@@ -178,3 +173,13 @@
   # ARM Architectural Timer Interrupt(GIC PPI) number
   gArmTokenSpaceGuid.PcdArmArchTimerSecIntrNum|29|UINT32|0x00000035  
   gArmTokenSpaceGuid.PcdArmArchTimerIntrNum|30|UINT32|0x00000036
+
+[PcdsFixedAtBuild.ARM]
+  # By default we do not do a transition to non-secure mode
+  gArmTokenSpaceGuid.PcdArmNonSecModeTransition|0x0|UINT32|0x0000003E
+  # If the fixed FDT address is not available, then it should be loaded below the kernel.
+  # The recommendation from the Linux kernel is to have the FDT below 16KB.
+  # (see the kernel doc: Documentation/arm/Booting)
+  gArmTokenSpaceGuid.PcdArmLinuxFdtMaxOffset|0x4000|UINT32|0x00000023
+  # The FDT blob must be loaded at a 64bit aligned address.
+  gArmTokenSpaceGuid.PcdArmLinuxFdtAlignment|0x8|UINT32|0x00000026

ArmPkg/Library/BdsLib/BdsLib.inf

@@ -76,6 +76,7 @@
 
   gArmTokenSpaceGuid.PcdArmMachineType
   gArmTokenSpaceGuid.PcdArmLinuxFdtMaxOffset
+  gArmTokenSpaceGuid.PcdArmLinuxFdtAlignment
   gArmTokenSpaceGuid.PcdArmLinuxKernelMaxOffset
   gArmTokenSpaceGuid.PcdArmLinuxAtagMaxOffset
   

ArmPkg/Library/BdsLib/BdsLinuxFdt.c

@@ -214,7 +214,9 @@ PrepareFdt (
 {
   EFI_STATUS            Status;
   EFI_PHYSICAL_ADDRESS  NewFdtBlobBase;
+  EFI_PHYSICAL_ADDRESS  NewFdtBlobAllocation;
   UINTN                 NewFdtBlobSize;
+  UINT32                FdtAlignment;
   VOID*                 fdt;
   INTN                  err;
   INTN                  node;
@@ -295,9 +297,15 @@ PrepareFdt (
   //
   NewFdtBlobSize = OriginalFdtSize + FDT_ADDITIONAL_ENTRIES_SIZE;
 
+  // If FDT load address needs to be aligned, allocate more space.
+  FdtAlignment = PcdGet32 (PcdArmLinuxFdtAlignment);
+  if (FdtAlignment != 0) {
+    NewFdtBlobSize += FdtAlignment;
+  }
+
   // Try below a watermark address
   Status = EFI_NOT_FOUND;
-  if (PcdGet32(PcdArmLinuxFdtMaxOffset) != 0) {
+  if (PcdGet32 (PcdArmLinuxFdtMaxOffset) != 0) {
     NewFdtBlobBase = LINUX_FDT_MAX_OFFSET;
     Status = gBS->AllocatePages (AllocateMaxAddress, EfiBootServicesData, EFI_SIZE_TO_PAGES(NewFdtBlobSize), &NewFdtBlobBase);
     if (EFI_ERROR(Status)) {
@@ -316,6 +324,11 @@ PrepareFdt (
     }
   }
 
+  NewFdtBlobAllocation = NewFdtBlobBase;
+  if (FdtAlignment != 0) {
+    NewFdtBlobBase = ALIGN (NewFdtBlobBase, FdtAlignment);
+  }
+
   // Load the Original FDT tree into the new region
   fdt = (VOID*)(UINTN)NewFdtBlobBase;
   err = fdt_open_into((VOID*)(UINTN)(*FdtBlobBase), fdt, NewFdtBlobSize);
@@ -530,7 +543,7 @@ PrepareFdt (
   return EFI_SUCCESS;
 
 FAIL_NEW_FDT:
-  gBS->FreePages (NewFdtBlobBase, EFI_SIZE_TO_PAGES (NewFdtBlobSize));
+  gBS->FreePages (NewFdtBlobAllocation, EFI_SIZE_TO_PAGES (NewFdtBlobSize));
 
 FAIL_ALLOCATE_NEW_FDT:
   *FdtBlobSize = (UINTN)fdt_totalsize ((VOID*)(UINTN)(*FdtBlobBase));